AutoNation, Fitbit rise; Copart, Microsoft fall

Stocks that moved substantially or traded heavily on Wednesday:

AutoNation Inc., up 82 cents to $43.91

CEO Mike Jackson is departing after almost two decades leading the nation's largest auto dealership chain.

Fitbit Inc., up 31 cents to $6.11

The maker of wearable exercise trackers launched a platform that offers personalized coaching.

MGM Resorts International, up 78 cents to $28.37

The New York Post reported that activist investor Starboard Value has taken a big stake in the casino operator.

Praxair Inc., up $6.20 to $164.37

News outlets reported the industrial gases company is moving closer to U.S. antitrust approval of its merger with Germany's Linde.

Copart Inc., down $8.59 to $55.58

The operator of online vehicle auctions reported earnings that fell short of analysts' estimates.

Danske Bank A/S, down 55 cents to $12.92

The CEO of Denmark's largest bank resigned after an internal report found many suspicious accounts in an Estonian subsidiary.

Microsoft Corp., down $1.51 to $111.70

Technology companies lagged the market on Wednesday.

Halliburton Co., up 90 cents to $40.06

Energy companies rose along with the price of crude oil.